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IEEE Transactions on Pattern Analysis... Jun 2024A desirable objective in self-supervised learning (SSL) is to avoid feature collapse. Whitening loss guarantees collapse avoidance by minimizing the distance between...
A desirable objective in self-supervised learning (SSL) is to avoid feature collapse. Whitening loss guarantees collapse avoidance by minimizing the distance between embeddings of positive pairs under the conditioning that the embeddings from different views are whitened. In this paper, we propose a framework with an informative indicator to analyze whitening loss, which provides a clue to demystify several interesting phenomena and a pivoting point connecting to other SSL methods. We show that batch whitening (BW) based methods do not impose whitening constraints on the embedding but only require the embedding to be full-rank. This full-rank constraint is also sufficient to avoid dimensional collapse. We further demonstrate that the stable rank of the embedding is invariant during training by gradient descent, given the assumption that embedding is updated with an infinitely small learning rate. Based on our analysis, we propose channel whitening with random group partition (CW-RGP), which exploits the advantages of BW-based methods in preventing collapse and avoids their disadvantages requiring large batch size. Experimental results on ImageNet classification and COCO object detection reveal that the proposed CW-RGP possesses a promising potential for learning good representations.
PubMed: 38905085
DOI: 10.1109/TPAMI.2024.3417438 -
JBJS Essential Surgical Techniques 2024A number of techniques have been described to enter the capsule and gain access to the hip joint during hip arthroscopy. Among these, the interportal and T-capsulotomies...
BACKGROUND
A number of techniques have been described to enter the capsule and gain access to the hip joint during hip arthroscopy. Among these, the interportal and T-capsulotomies are the most commonly utilized; however, these approaches transect the iliofemoral ligament, which normally resists anterior subluxation and stabilizes extension. Thus, these approaches may introduce capsuloligamentous instability and have been associated with complications such as dislocation, postoperative pain, microinstability, seroma, and heterotopic ossification. Although prior literature has demonstrated durable mid-term results for patients undergoing capsulotomies with capsular closure, avoidance of iatrogenic injury to the hip capsule altogether is preferable. Thus, the puncture capsulotomy technique we present is minimally invasive, preserves the biomechanics of the hip joint and capsule without disrupting the iliofemoral ligament, and allows for appropriate visualization of the joint through placement of multiple small portals.
DESCRIPTION
Following induction of anesthesia and with the patient supine on a hip traction table, the nonoperative leg is positioned at 45° abduction with support of a well-padded perineal post, and the operative hip is placed into valgus against the post. Intra-articular fluid distention with normal saline solution is utilized to achieve approximately 9 mm of inferior migration of the femoral head and decrease risk of iatrogenic nerve injury. Then, under fluoroscopic guidance, an anterolateral portal is created 1 cm anterior and 1 cm superior to the greater trochanter at an approximately 15° to 20° angle. Second, via arthroscopic visualization, the anterior portal is created 1 cm distal and 1 cm lateral to the intersection of a vertical line drawn at the anterior superior iliac spine and a horizontal line at the level of the anterolateral portal. Third, equidistant between the anterior and anterolateral portals, the mid-anterior portal is created distally. Finally, at one-third of the distance between the anterior superior iliac spine and the anterolateral portal, the Dienst portal is created. Thus, these 4 portals form a quadrilateral arrangement through which puncture capsulotomy can be performed.
ALTERNATIVES
Alternative approaches to the hip capsule include interportal and T-capsulotomies, with or without capsular closure. Although the most frequently utilized, these approaches transect the iliofemoral ligament and thus may introduce capsuloligamentous instability.
RATIONALE
The puncture capsulotomy technique has the advantage of maintaining the integrity of the capsule through the placement of 4 small portals. The technique does not transect the iliofemoral ligament and thus does not introduce capsuloligamentous instability. Furthermore, although good mid-term outcomes have been reported with capsular closure, the present technique avoids creating unnecessary injury to the capsule and complications of an unrepaired capsule or, conversely, of plication.
EXPECTED OUTCOMES
Patients who underwent the puncture capsulotomy technique showed significant improvements in multiple functional outcome scores at a mean follow-up of 30.4 months, including the International Hip Outcome Tool (iHOT-33) (39.6 preoperatively to 76.1 postoperatively), Hip Outcome Score-Activities of Daily Living subscale (HOS-ADL) (70.0 to 89.3), HOS Sport-Specific Subscale (HOS-SSS) (41.8 to 75.7), and modified Harris hip score (mHHS) (60.1 to 84.9). At 2 years postoperatively with respect to iHOT-33, 81.0% of patients achieved the minimal clinically important difference, 62.0% achieved the patient acceptable symptom state, and 58.9% achieved substantial clinical benefit. In addition, mean visual analog scale pain scores improved significantly over the follow-up period (6.3 to 2.2; p < 0.001). Finally, there were zero occurrences of infection, osteonecrosis of the femoral head, dislocation or instability, or femoral neck fracture in patients treated with puncture capsulotomy.
IMPORTANT TIPS
Anterolateral portal placement should be performed using the intra-articular fluid distention technique with fluoroscopy to avoid risk of iatrogenic labral damage and distraction-induced neurapraxia. Subsequent portals must then be placed under direct arthroscopic visualization.On establishment of the anterolateral portal, the scope should be switched to the anterior portal to ensure that the anterolateral portal has not been placed through the labrum and to adjust its placement to better access pathology. This portal, as well as all others, may be subsequently modified by adjusting the angle of the cannula, without making a new skin incision.If a cam lesion is located more anteromedially or posterolaterally, an additional accessory portal may be made distal or proximal to the anterolateral portal, respectively, in order to enhance visualization.Intermittent traction is utilized throughout the surgery. No traction is utilized during preparing and draping, suture tensioning and tie-down, and femoroplasty, with minimal traction during acetabuloplasty; these precautions serve to prevent iatrogenic superficial peroneal nerve injury.There can be a steep learning curve for this technique. In particular, greater surgical experience is required to perform adequate femoral osteoplasty for large cam lesions with this approach.Instrument maneuverability and visualization can be somewhat constrained with this approach.It is more difficult to perform certain procedures with this technique, including segmental and circumferential labral reconstructions, particularly with remote grafts.
ACRONYMS AND ABBREVIATIONS
iHOT-33 = International Hip Outcome Tool-33HOS-ADL = Hip Outcome Score-Activities of Daily Living subscaleHOS-SSS = Hip Outcome Score-Sport-Specific SubscaleAP = anteroposteriorMRA = magnetic resonance arthrogramMRI = magnetic resonance imagingCT = computed tomographyASIS = anterior superior iliac spinemHHS = modified Harris hip score.
PubMed: 38903605
DOI: 10.2106/JBJS.ST.23.00061 -
Frontiers in Neuroscience 2024Reward-seeking behavior is frequently associated with risk of punishment. There are two types of punishment: positive punishment, which is defined as addition of an...
Reward-seeking behavior is frequently associated with risk of punishment. There are two types of punishment: positive punishment, which is defined as addition of an aversive stimulus, and negative punishment, involves the omission of a rewarding outcome. Although the medial prefrontal cortex (mPFC) is important in avoiding punishment, whether it is important for avoiding both positive and negative punishment and how it contributes to such avoidance are not clear. In this study, we trained male mice to perform decision-making tasks under the risks of positive (air-puff stimulus) and negative (reward omission) punishment, and modeled their behavior with reinforcement learning. Following the training, we pharmacologically inhibited the mPFC. We found that pharmacological inactivation of mPFC enhanced the reward-seeking choice under the risk of positive, but not negative, punishment. In reinforcement learning models, this behavioral change was well-explained as an increase in sensitivity to reward, rather than a decrease in the strength of aversion to punishment. Our results suggest that mPFC suppresses reward-seeking behavior by reducing sensitivity to reward under the risk of positive punishment.
PubMed: 38903603
DOI: 10.3389/fnins.2024.1412509 -
Archives of Sexual Behavior Jul 2024While intimate partner violence is now recognized as a major societal and international issue, sexual violence between partners remains understudied despite its...
While intimate partner violence is now recognized as a major societal and international issue, sexual violence between partners remains understudied despite its significant prevalence rates and the specific contexts in which it occurs. The aim of this study was to analyze the links between different dimensions of sexual consent and sexual coercion experienced within intimate relationships in order to identify targets for prevention campaigns. The study was carried out during a time of transition in the sociopolitical and legislative context in Belgium linked to the implementation of a reform to the sexual criminal law, which has made the expression of sexual consent central to the qualification of sexual offenses. A total of 431 young adults (88.40% female; M = 22.19 years; SD = 1.79) were recruited from the general population through an online survey to analyze the links between attitudes and beliefs toward sexual consent, attachment style, mental health, and sexual victimization between partners. Results showed that a lack of perceived behavioral control over establishing sexual consent, as well as the avoidance of intimacy, predicted sexual victimization. The clinical implications of these findings are discussed and potential public policy responses for prevention and awareness are suggested. Future research should further investigate and conceptualize sexual consent as it relates to sexual coercion in a more representative sample from an intersectional perspective.
Topics: Humans; Female; Male; Coercion; Intimate Partner Violence; Young Adult; Adult; Sexual Partners; Sexual Behavior; Belgium; Sex Offenses; Attitude; Crime Victims; Surveys and Questionnaires; Adolescent
PubMed: 38902488
DOI: 10.1007/s10508-024-02890-w -
Progress in Neuro-psychopharmacology &... Jun 2024The ventral pallidum (VP) receives its primary inputs from the nucleus accumbens (NAC) and the basolateral amygdala (BLA). We demonstrated recently that in the VP, the...
The ventral pallidum (VP) receives its primary inputs from the nucleus accumbens (NAC) and the basolateral amygdala (BLA). We demonstrated recently that in the VP, the D2 DA receptor (DR) agonist quinpirole dose-dependently facilitates memory consolidation in inhibitory avoidance and spatial learning. In the VP, DR can be found both on NAC and BLA terminals. According to our hypothesis, quinpirole microinjected into the VP can facilitate memory consolidation via modulation of synaptic plasticity on NAC and/or BLA terminals. The effect of intra-VP quinpirole on BLA-VP and NAC shell-VP synapses was investigated via a high frequency stimulation (HFS) protocol. Quinpirole was administered in three doses into the VP of male Sprague-Dawley rats after HFS; controls received vehicle. To examine whether an interaction between the NAC shell and the BLA at the level of the VP was involved, tetrodotoxin (TTX) was microinjected into one of the nuclei while stimulating the other nucleus. Our results showed that quinpirole dose-dependently modulates BLA-VP and NAC shell-VP synapses, similar to those observed in inhibitory avoidance and spatial learning, respectively. The lower dose inhibits BLA inputs, while the larger doses facilitates NAC shell inputs. The experiments with TTX demonstrates that the two nuclei do not influence each others' evoked responses in the VP. Power spectral density analysis demonstrated that independent from the synaptic facilitation, intra-VP quinpirole increases the amplitude of gamma frequency band after NAC HFS, and BLA tonically suppresses the NAC's HFS-induced gamma facilitation. In contrast, HFS of the BLA results in a delayed, transient increase in the amplitude of the gamma frequency band correlating with the LTP of the P1 component of the VP response to BLA stimulation. Furthermore, our results demonstrate that the BLA plays a prominent role in the generation of the delta oscillations: HFS of the BLA leads to a gradually increasing delta frequency band facilitation over time, while BLA inhibition blocks the NAC's HFS induced strong delta facilitation. These findings demonstrate that there is a complex interaction between the NAC shell region and the VP, as well as the BLA and the VP, and support the important role of VP DRs in the regulation of limbic information flow.
PubMed: 38901759
DOI: 10.1016/j.pnpbp.2024.111059 -
Preventive Medicine Jun 2024To investigate the relationship between Body Mass Index (BMI) and adherence to recommended screening tests, addressing gaps in previous literature by utilizing a large...
OBJECTIVE
To investigate the relationship between Body Mass Index (BMI) and adherence to recommended screening tests, addressing gaps in previous literature by utilizing a large cohort, while considering longitudinal changes in weight and the type of screening.
METHODS
Data from Clalit Health Services in Israel were retrospectively analyzed, including participants aged 50 and above from 2002 to 2021. BMI measurements and various screening test records were examined. Generalized Estimating Equations were employed for analysis, adjusting for potential confounding variables, including age, gender, geographic location, and socioeconomic status.
RESULTS
The study included 634,879 participants with 4,630,030 BMI measurements and 56,453,659 test records. Participants were categorized into BMI cohorts at the time of the test, with overweight and obese individuals showing lower odds of undergoing intimate examination-based screening tests (mammography, PAPS, and skin examination), as opposed to higher odds of several non-intimate tests (e.g., diabetes and eye disorder screenings).
DISCUSSION
Our findings suggest that individuals with overweight and obesity are less likely to undergo screenings involving intimate physical examinations, potentially due to weight stigma and discomfort. This avoidance behavior may contribute to increased morbidity rates in these populations. Interventions addressing weight stigma, improving access to care, and enhancing patient engagement are warranted.
PubMed: 38901741
DOI: 10.1016/j.ypmed.2024.108045 -
Frontiers in Robotics and AI 2024Soft robots exhibit complex nonlinear dynamics with large degrees of freedom, making their modelling and control challenging. Typically, reduced-order models in time or...
Soft robots exhibit complex nonlinear dynamics with large degrees of freedom, making their modelling and control challenging. Typically, reduced-order models in time or space are used in addressing these challenges, but the resulting simplification limits soft robot control accuracy and restricts their range of motion. In this work, we introduce an end-to-end learning-based approach for fully dynamic modelling of any general robotic system that does not rely on predefined structures, learning dynamic models of the robot directly in the visual space. The generated models possess identical dimensionality to the observation space, resulting in models whose complexity is determined by the sensory system without explicitly decomposing the problem. To validate the effectiveness of our proposed method, we apply it to a fully soft robotic manipulator, and we demonstrate its applicability in controller development through an open-loop optimization-based controller. We achieve a wide range of dynamic control tasks including shape control, trajectory tracking and obstacle avoidance using a model derived from just 90 min of real-world data. Our work thus far provides the most comprehensive strategy for controlling a general soft robotic system, without constraints on the shape, properties, or dimensionality of the system.
PubMed: 38899065
DOI: 10.3389/frobt.2024.1403733 -
Revue Medicale Suisse Jun 2024Pain has multiple consequences, forcing people to change the way they carry out their activities (domestic, work, leisure, social). Classically, three behavioural...
Pain has multiple consequences, forcing people to change the way they carry out their activities (domestic, work, leisure, social). Classically, three behavioural strategies have been described: avoidance, modulation, and persistence. Recent research suggests that the use of these strategies is more complex and subtle than previously imagined. Identifying behavioural activity strategies early in the management process with simple, precise, and concrete questions is particularly useful for adapting treatment plans. From a therapeutic point of view, the recommendations for promoting activity are both to choose activities that are valued by the patient in order to reinforce his or her commitment, and to encourage flexibility in the choice of behavioural strategies depending on the context.
Topics: Humans; Pain; Pain Management; Behavior Therapy
PubMed: 38898754
DOI: 10.53738/REVMED.2024.20.879.1194 -
Archives of Sexual Behavior Jun 2024Compulsive sexual behavior disorder (CSBD) was previously considered an attachment disorder, while emotion dysregulation was thought to potentially be a key...
The Associations Between Attachment Insecurity and Compulsive Sexual Behavior Disorder or Problematic Pornography Use: The Mediating Role of Emotion Regulation Difficulties.
Compulsive sexual behavior disorder (CSBD) was previously considered an attachment disorder, while emotion dysregulation was thought to potentially be a key characteristic of it. However, this theoretical model was not tested in previous empirical research. In our cross-sectional study, we tested whether emotional regulation (ER) difficulties can be adopted as an explanatory mechanism for the relationships between attachment avoidance and anxiety, as well as CSBD and its most prevalent behavioral presentation-problematic pornography use (PPU). Participants (n = 1002; M = 50.49 years, SD = 13.32; men: 50.2%) completed an online survey regarding the investigated variables. In mediation analyses, attachment avoidance and anxiety were treated as simultaneous predictors, ER difficulties as a mediating variable, with CSBD/PPU severity as dependent variables. Emotion regulation difficulties and attachment anxiety had a direct positive effect on both CSBD and PPU. The direct effect of attachment avoidance on PPU was non-significant, and significant for CSBD depending on the measure used. Moreover, all the relationships between both insecure attachment dimensions and CSBD/PPU symptom severity were at least partially mediated by ER difficulties. Our results corroborate the theoretical claim that ER difficulties may be a useful framework for explaining the impact of attachment insecurity on CSBD/PPU. Theoretical and practical implications of the findings are discussed.
PubMed: 38898361
DOI: 10.1007/s10508-024-02904-7 -
BioRxiv : the Preprint Server For... Jun 2024Many psychiatric disorders involve excessive avoidant or defensive behavior, such as avoidance in anxiety and trauma disorders or defensive rituals in...
OBJECTIVE
Many psychiatric disorders involve excessive avoidant or defensive behavior, such as avoidance in anxiety and trauma disorders or defensive rituals in obsessive-compulsive disorders. Developing algorithms to predict these behaviors from local field potentials (LFPs) could serve as foundational technology for closed-loop control of such disorders. A significant challenge is identifying the LFP features that encode these defensive behaviors.
APPROACH
We analyzed LFP signals from the infralimbic cortex and basolateral amygdala of rats undergoing tone-shock conditioning and extinction, standard for investigating defensive behaviors. We utilized a comprehensive set of neuro-markers across spectral, temporal, and connectivity domains, employing SHapley Additive exPlanations for feature importance evaluation within Light Gradient-Boosting Machine models. Our goal was to decode three commonly studied avoidance/defensive behaviors: freezing, bar-press suppression, and motion (accelerometry), examining the impact of different features on decoding performance.
MAIN RESULTS
Band power and band power ratio between channels emerged as optimal features across sessions. High-gamma (80-150 Hz) power, power ratios, and inter-regional correlations were more informative than other bands that are more classically linked to defensive behaviors. Focusing on highly informative features enhanced performance. Across 4 recording sessions with 16 subjects, we achieved an average coefficient of determination of 0.5357 and 0.3476, and Pearson correlation coefficients of 0.7579 and 0.6092 for accelerometry jerk and bar press rate, respectively. Utilizing only the most informative features revealed differential encoding between accelerometry and bar press rate, with the former primarily through local spectral power and the latter via inter-regional connectivity. Our methodology demonstrated remarkably low time complexity, requiring 110 ms for training and 1 ms for inference.
SIGNIFICANCE
Our results demonstrate the feasibility of accurately decoding defensive behaviors with minimal latency, using LFP features from neural circuits strongly linked to these behaviors. This methodology holds promise for real-time decoding to identify physiological targets in closed-loop psychiatric neuromodulation.
PubMed: 38895388
DOI: 10.1101/2024.06.06.597165